1) file complaint with muncipal corporation against society refusal to take action on leakages from neighbour flat 

2) you can also file complaint against society before consumer forum seek orders to direct society to direct neighbour to plug the leakages 

3) it is society responsibility to repair the terrace as it forms part of common area 

4) also seek litigation costs and compensation for mental torture under gone by you 

See you can give a legal notice to the society and the above flat owner asking them to repair the Terrace and seeking damages for the loss if on notice the society and the person fails to repair you can file a suit seeking direction to repair the roof and seeking damages. 

Complain to police for creating nuisance and mischief. When polcie will call him, will understand.

Its better you both approach society and try to share the expenses equally in 3 shares. Otherwise this will continue. You need to approach civil court if you want to dispute the same

contact   alocal lawyer 

issue legal notice to neighbour to repair the terrace 

if he fails to do so society has to take action against flat owner 

if society fails to do so act as mentioned herein above 

Even the side wall erected to his flat to support the terrace.

1. First of all you got to get the situation assessed by a civil works (construction/renovation) professional, whether the leakage is due to the terrace flat above you. 
2. If the civil works guy certifies (ie give his opinion in writing) that your troubles cannot be resolved unless repairs are carried out in the terrace flat above, then you can think of legal action. 
3. You must get a legal notice served upon the member above, and also your housing society, through your counsel (Advocate), to get the repairs done; intimating them that you are well within your rights to move the cooperative court against them, if they don't comply. 
4. After 30 days of service of legal notice, if your troubles aren't resolved, you will instruct your counsel to move the cooperative court. 
5. I'm prepared to handle your case as your counsel (Advocate). However, I require an exhaustive consultation session with you first, to brief you on detail. I'm based in Mumbai just as you are, so it shouldn't be much difficult for you to visit me for exhaustive consultation.

Dear Sir

You may lodge the complaint with the secretary of your association for taking necessary action in this regard, if this fails to invoke any response, you may issue legal notice to the owner and the secretary after which you can initiate suitable legal action in appropriate legal forum/court.

See if both society and said person is not ready to listen then in that case it is better to give notice and proceed with the suit.

- As per law, the upper floor owner is responsible for repairing the water leakage .

- You should first serve him with a legal notice through an advocate asking him to repair/rectify the cause of water leakage in your flat.

- One copy of the same should also serve to the Society managing Commitee as well. 

- If, within 15 days of time , they refuse to do the same, then you should file a suit for Injunction for the direction to the upper owner .

- Dont worry , you will get relief in your favour.

You can appoint am expert if the leakage is from side walls society has to repair the same as it's common area. Otherwise you both hand to bear it

You can send notice through Lawyer to that Flat Owner contending that repair the leakage within stipulated time and if he denying to do that then you can move to civil court for filing suit of mandatory injunction against that flat owner

Owner above your flat is liable to repair any leakage from his flat which is causing damage to your property.

You have to file a suit against the flat owner and society for repair of terrace and compensation For damage caused to kitchen and bedroom due to leakage of roof.

Actually the upper floor owner is responsible for carrying out the repair to his toilet etc.,  so that the seepage do not come from his house to the lower house.

In some of the RWAs the owners agree to bear the cost to 50-50 for the expenses for the convenience.  

But legally speaking the upper floor owner has to bear the complete costs towards this.

In case the upper floor owner is not ready to bear the cost, then the sufferer can get it repaired at his cost and go to court to recover the same along with the litigation cost.

Alternately the association is liable to take the responsibility to recover by taking appropriate action against the upper floor owner if the sufferer owner gives a letter to this effect. 

The owner sufferer can approach consumer court also for getting a direction to the upper floor owner to get his toilet or the place from where the leakage or seepage starts to get it repaired.

Even though the seepage is from the side walls, the water seeps into your floor from his house hence he is held responsible for the leakage or seepage.

Therefore he will be held responsible for getting the same repaired.